Movie release date

**What does your instant answer do?**
Show a movie release date.

**What problem does your instant answer solve (Why is it better than organic links)?**
It shows the correct date, thus saving valuable time.

**What is the data source for your instant answer? (Provide a link if possible)**
TheMovieDb.

**Why did you choose this data source?**
They are community-driven and have a well-documented API!

**Are there any other alternative (better) data sources?**
IMDbAPI potentially, but it's lacking documentation.

**What are some example queries that trigger this instant answer?**
"when did lion king come out?"
"batman vs superman premiere"

**Which communities will this instant answer be especially useful for? (gamers, book lovers, etc)**
Movie-goers, trivia obsessors

**Is this instant answer connected to an [Ideas.DuckDuckHack](https://duckduckhack.uservoice.com/forums/5168-ideas-for-duckduckgo-instant-answer-plugins) or [Duck.co](http://duck.co/) thread?**
[Yup](https://duck.co/ideas/idea/26/show-release-date-for-games-movies-and-tv-shows).

**Which existing instant answers will this one supersede/overlap with?**
The movie spice, if showed a release date.

**Are you having any problems? Do you need our help with anything?**
Checking over it would be cool, and feel free to try it on some obscure movies.
![screenshot](https://f.cloud.github.com/assets/2399307/1651531/2a2bdb32-5adf-11e3-8f11-1447556c2036.png)

##Checklist
```
[] Added metadata and attribution information
[✔] Wrote test file and added to t/ directory
[✔] Verified that instant answer adheres to design guidelines(https://github.com/duckduckgo/duckduckgo-documentation/blob/master/duckduckhack/styleguides/design_styleguide.md)
[✔] Tested cross-browser compatability

    Please let us know which browsers/devices you've tested on:
    - Manjaro Linux
        [✔] Chromium 
        [✔] Firefox
```